EvoWalk, Quix teams talk about progress in Toyota Mobility Unlimited Challenge

Mobility is more than autonomous vehicles or delivery robots; it also includes the use of assistive technologies for individuals. The Toyota Mobility Unlimited Challenge is a $4 million international competition launched in 2017 to support the development of systems to aid people with lower-limb paralysis. The challenge had originally planned to announce the $1 million first-prize winner in September 2020, but the COVID-19 pandemic delayed that to December.

The Toyota Mobility Foundation and Nesta Challenge Price Centre announced five finalist teams at CES 2020 in January. Two of the teams are based in the U.S., and The Robot Report caught up with them to learn about the status of their projects.

Berkeley, Calif.-based Evolution Devices Inc. is developing EvoWalk, a wearable device that uses sensors and artificial intelligence to predict the user’s gait and electrically stimulate his or her muscles. The Florida Institute for Human and Machine Cognition (IHMC) in Pensacola, Fla., and MYOLYN in Gainesville, Fla., have been working on Quix, a powered exoskeleton.

Quix develops with user input

IHMC and MYOLYN have been working on a robotic exoskeleton with motors at the hips, knees, and ankles, as well as additional actuators to help people with lower-limb paralysis move faster and with more stability and agility than with current devices.

“We’ve gone as far as we can with wheelchairs. Toyota‘s Mobility Unlimited Challenge aligns with our goals for exoskeletons,” said Dr. Robert Griffin, a research scientist at IHMC and project led for the Quix exoskeleton. “It started out as a pretty dumb device with not a lot of sensors, feedback, or intelligence.”

“Because of the competition’s timeline, we really had to put together the development and minimum algorithms to get it done,” Griffin explained. “We joined the challenge from the Discovery Award two years ago, and it took time to redesign actuation and engage with potential end users on the tasks they identified as the most important. We found that a lot of able-bodied people would prioritize different things. We thought that a normal walking speed would be a higher priority than the ability to use the bathroom, which was actually the highest. In fact, walking was fourth.”

“The physical device came together in January, and we got it tested from March or April to September,” he said. “We now have a device to develop ideas and are adding elements to the exoskeleton so it’s not a burden for a pilot to use. We’re also leveraging our experience from humanoid robots, such for figuring out where to step in cluttered environments.”

Mark Daniel was an 18-year-old welder in 2007 when he lost the use of his legs in an automotive accident. He began evaluating IHMC’s first-generation exoskeleton in 2010 and won a silver medal in the 2016 Cybathlon. Daniel is the “test pilot” for Quix.

“They initially developed their exoskeleton without input from people with spinal cord injuries,” he recalled. “There were a lot of things they didn’t know and I didn’t know, but they went back to the drawing board. I’ve worked with them every step of the way, from being hands-on with software design to how to interact with the cuffs to don the device.”

“I’ve had several conversations with Brandon [Peterson, lead controls engineer at IHMC], who knew what I needed adjusted,” Daniel said. “Quix is getting closer and closer to how the body moves. I want to keep myself in shape to help make the device easier for others to use. It currently takes a lot of upper-body strength and agility, but I’m helping to push the device to be more environmentally aware and get more feedback from sensors.”

“It’s crucial to have users in the feedback loop in the development of the device,” Peterson added. “It’s even more crucial to have feedback from the user after testing. Mark has demonstrated fearlessness and willingness to strap into the device. Improving sensory substitution helps with restoring a sense of balance.”

EvoWalk continues to evolve

“We’ve been working pretty hard,” said Pierluigi Mantovani, co-founder and CEO of Evolution Devices. “For the first few months of the year, we were developing different prototypes and working with different people. We did a three eight-week pilots right before the pandemic hit. We had pretty amazing results from the device, which extracted metrics on how people are walking and sent information back to the patient and clinician.”

The company then moved to teletrials for EvoWalk because of the novel coronavirus. “Data is a big part of the value we add, not just for the physical therapists, but also for the patients,” Mantovani said. “We didn’t know it would be fully virtual, but it has worked from the beginning.”

“COVID-19 has pushed us to do remote patient monitoring, but it has become a valuable tool to do assessments continuously,” said Andrew Ekelem, chief product officer at Evolution Devices.

Sharing gait data with patients can also help keep them motivated during therapy, added Mantovani. “We’re still building the app to show data to the patient,” he said.

“The goals feature increases the number of steps per week. We’ve created fun things to do around status and are applying them to rehab,” said Ekelem. “We’ve made aesthetic improvements to the physical device and application as well. In the last EvoWalk prototype, we’ve been testing where lights and buttons should go and the interface with phones.”

“We spent a substantial amount of time on and have a team just for metrics,” noted Juan M. Rodriguez, chief technology officer of Evolution Devices. “We looked at a healthy person’s walking style, knee flection, and measures of balance walking throughout the day. No others can do this as accurately as with EvoWalk, and we validate with motion capture.”

In September, Evolution Devices received a National Science Foundation (NSF) Small Business Innovation Research (SBIR) grant for $224,990 to conduct research and development work on EvoVision, which it described as “a markerless motion-capture system that will automate gait analysis for rehabilitation centers.”

Quix team iterates device

“A lot of our stuff is built from off-the-shelf components,” said Vishnu Subra Mani, lead mechanical engineer on the Quix team. “The total actuation package was designed in house over the past six years, and we used a linear linkage actuator from NASA Johnson Space Center in the Mina exoskeleton [a predecessor of Quix].”

“We also use custom carbon fiber for the hips, anchor, and back,” he said. “We took a 3D scan of Mark’s body. We’re developing a personal mobility device that just needs to fit the wearer, so it’s not so much for outpatient or rehab use.”

“With preprinted metal and some post-machining, we have a development platform to push the technology forward,” said Peterson. “We’re also pushing the algorithms for smart exoskeletons. There are more boundaries and degrees of freedom we can push.”

“For example, adding adduction and abduction took a huge load off of me physically from having to move the device and shift my body weight with each swing,” said Daniel. “It was a massive improvement, working at 75% to 80% less capacity than with Mina.”

The next milestone is to make the device more robust on uneven terrain, said Griffin. “Our dream would be to have Mark take it on nature trails,” he said.

“We’re really focused on getting the technology working, with an eye toward commercialization and productization,” he said. “We’re in talks with MYOLYN to see what they want and have partnered with the Andrews Institute for Orthopaedics & Sports Medicine. If we win the Toyota challenge, we’ll use he money to first push the software forward on existing hardware.”

“Over the next couple of years, we hope to get the cost comparable to that of an entry-level car,” Griffin said. “As robotics is embraced by more of society, costs for small-scale motors and power systems should decrease rapidly. Healthcare providers and insurance systems will see the benefits of the device. Just improving posture will reduce long-term health costs.”

Evolution Devices looks ahead with EvoWalk

Evolution Devices is working to freeze EvoWalk’s design by the end of the year and get clearance from the U.S. Food and Drug Administration by the second quarter of 2021, said Mantovani.

“We’ve launched a clinic internally as part of our remote pilots, and we brought on Lisa Donahue as our director of clinical services,” he said. “Part of the reason why we’re creating our own clinic is to get things into the hands of patients easier and keep the price tag as low as we can. We’re also looking to partner with big institutes on remote physical therapy.”

“Our device is unique in that it helps people perform better,” said Ekelem. “For cost and complexity reasons, the number of sensors is limited, but we could get even better data with more sensors and maximizing capabilities with a single sensor.”

In addition to therapeutic uses, could EvoWalk benefit other applications, such as sports medicine? “Our big vision is to learn and teach all kinds of movements,” replied Mantovani. “With our gait lab, we’ve built up the infrastructure for wearables to collect all kinds of data. They could move into other spaces to help more people.”

“We have a vision to extend to other parts of the body,” said Rodriguez. “EvoWalk is pretty modular, and we could use the same hardware and put it on different muscles and just retrain the algorithm. Innovation is not just our technology; it’s also our business model.”